Related Variables
| chgtime | Over the last month, have you experienced: your bedtime changed by two or more hours | Lab Visit | |
| dayhrs | Number of hours of sleep during the weekdays | Lab Visit | |
| dayslp_dur_hr | Calculated sleep duration on weekdays | Lab Visit | |
| end_dur_hr | Calculated sleep duration on weekends | Lab Visit | |
| endhrs | How many hours of sleep on weekend days | Lab Visit | |
| sleeptime_hr | Calculated sleep duration on all days | Lab Visit | |
| tothrslp | How many total hours of actual sleep do you get in a 24-hour period (including naps) | Lab Visit | |
| bedalcl | Do you drink 2 hours before bed | Lab Visit/Medical History | |
| ai_all |
Arousal Index
Total number of arousals per hour of sleep. Ratio of count of arousals to total sleep time in hours. |
Polysomnography/Arousals | |
| ai_nrem |
Arousal Index (NREM)
Non-REM Arousal Index - total arousals in non-REM sleep per hours of non-REM sleep |
Polysomnography/Arousals | |
| ai_rem |
Arousal Index (REM)
REM Arousal Index - total arousals in REM sleep per hours of REM sleep |
Polysomnography/Arousals | |
| oahi3 |
Obstructive apnea (all desaturations) hypopnea (3% desaturation) index
Obstructive apnea hypopnea index {[(total number of obstructive apneas) + (total number of hypopneas associated with >= 3% desaturation)] / (hours of sleep)} |
Polysomnography/Respiratory Events/Indexes | |
| rdi4p |
Overall RDI at 4% oxygen desaturation
Ratio of the count of all apneas (central and obstructive) and hypopneas associated with at least a 4% oxygen desaturation to the total sleep time expressed in hours |
Polysomnography/Respiratory Events/Indexes | |
| abdodur |
PSG Quality Assessment: hours of usable abdomen effort
Number of hours of usable signal from abdominal effort belt as assessed by scorer. |
Polysomnography/Signal Quality | |
| airdur |
PSG Quality Assessment: hours of usable airflow
Number of hours of usable signal from airflow sensor (thermistor) as assessed by scorer. |
Polysomnography/Signal Quality | |
| candur |
PSG Quality Assessment: hours of usable cannula
Number of hours of usable signal |
Polysomnography/Signal Quality | |
| chestdur |
PSG Quality Assessment: hours of usable chest effort
Number of hours of usable signal from thoracic effort belt as assessed by scorer. |
Polysomnography/Signal Quality | |
| chindur |
PSG Quality Assessment: hours of usable chin
Number of hours of usable signal from chin (EMG) lead as assessed by scorer. |
Polysomnography/Signal Quality | |
| eeg1dur |
PSG Quality Assessment: hours of usable EEG1
Number of hours of usable signal from EEG1 lead as assessed by scorer. |
Polysomnography/Signal Quality | |
| eeg2dur |
PSG Quality Assessment: hours of usable EEG2
Number of hours of usable signal from EEG2 lead as assessed by scorer. |
Polysomnography/Signal Quality | |
| eogldur |
PSG Quality Assessment: hours of usable EOG L
Number of hours of usable signal from left eye (EOG) lead as assessed by scorer. |
Polysomnography/Signal Quality | |
| eogrdur |
PSG Quality Assessment: hours of usable EOG R
Number of hours of usable signal from right eye (EOG) lead as assessed by scorer. |
Polysomnography/Signal Quality | |
| hrdur |
PSG Quality Assessment: hours of usable HR
Number of hours of usable signal from heart rate (ECG) leads as assessed by scorer. |
Polysomnography/Signal Quality | |
| legldur |
Hours of usable legL
Hours of usable L leg |
Polysomnography/Signal Quality | |
| legrdur |
Hours of usable legR
Hours of usable R leg |
Polysomnography/Signal Quality | |
| oximdur |
PSG Quality Assessment: hours of usable oximetry
Number of hours of usable signal from oximeter as assessed by scorer. |
Polysomnography/Signal Quality | |
| pulsedur |
PSG Quality Assessment: hours of usable pulse
Number of hours of usable signal from pulse sensor as assessed by scorer. |
Polysomnography/Signal Quality | |
| pwfdur |
PSG Quality Assessment: hours of usable PWF
Number of hours of usable signal |
Polysomnography/Signal Quality | |
| snordur |
Hours of usable snore
Hours of usable snore mic |
Polysomnography/Signal Quality | |
| sumdur |
Hours of usable SUM
Hours of usable SUM channel |
Polysomnography/Signal Quality | |
| pctlt90 |
Percent of sleep time with less than 90% SaO2
Ratio of the number of minutes with oxygen saturation under 90% to the total sleep time expressed in hours. |
Polysomnography/Sleep Architecture | |
| napdy1h | Hours of nap1 | Sleep Diary | |
| napdy2h | Hours of nap 2 | Sleep Diary | |
| napdy3h | Hours of nap 3 | Sleep Diary | |
| slpth | Hours sleep last night | Sleep Diary | |
| totawh | Hours spent awake | Sleep Diary |